SU126040A1 - Electronic switch - Google Patents

Description

Electronic switches are known for simultaneous switching of several prices in which the switched low frequency signals are preliminarily converted into p-high-frequency signals with the subsequent conversion of these signals to low-frequency voltage.

The disadvantage of such switches is the presence of a large number of switching elements, which complicates the device circuit; i reduces the reliability of its operation.

To simplify the switch design and increase the reliability of its operation, the device described uses double frequency conversion of incoming signals, with separate heterodyne used in the primary conversion unit, and a switched local oscillator used in the secondary conversion unit followed by filtering and detection.

In the drawing, a block diagram of the described device is shown, comprising FIVE inputs and five channel outputs.

Coming signals are fed to the inputs of -5 channels. At the frequency of modulators 6-10 and high-frequency local oscillators 11- / 5, the first frequency conversion of the incoming signals is performed.

The frequencies of the local oscillators 11-15 differ one relative to another by the same amount. The high frequency signals of the local oscillators, modulated by incoming signals, are filtered by narrowband filters 16–20, amplified by a wideband high frequency amplifier 21, and fed to mixer 22. The second input of mixer 22 provides signals with a frequency f of the local oscillator 23 switched in frequency using a control circuit 24. The local oscillator 23 can generate signals of five different frequencies L ,, fz, and / that differ from one another by the same amount. After the secondary conversion by mixer 22, the signals are fed to filters 25-33, detected by demodulators 34-38, amplified by low-frequency amplifiers 39-43, and fed to outputs 44-48 channels.

With an appropriate choice of the pass frequencies of the filters 25- 33, when a signal with a frequency fg ,, generated by the local oscillator 23 is applied to the mixer 22, the signal from the input J through the filter 25 will go to output 44, from-to input 2 through filter 26 to output 45, from the input 3 through the filter 28 to output 46, from input 4 through the filter 30 to output 47 and from input 5 through the filter 32 to exit 48. When a signal with a frequency / g generated by the local oscillator 25 is applied to the mixer 22, the signal from the input / through filter 26 enters output 45, from input 2 through filter 28 to output 46, from input 3 through filter 30 to exit 47, from input 4 through filter: 35 to output 48 and from input 5 through a filter to 25 to the output, and so on. In this way, switching is carried out in the sequence shown in Table No. 1.

Table number | one

 Further, the switching process is repeated. If necessary, the number of channels can be increased. Since the channel switching is carried out in the high-frequency path by changing the frequency common to all the local oscillator channels, the level of switching circuits; ad.ex- is very low;

Subject invention

A switchboard switch, characterized in that, in order to switch a large number of chains at a time, with a small number of, edements ,. a double frequency conversion is applied to incoming frequencies of € 1 ddado. in this case, for the first transformation, separate D | DN: p | az channels of high-frequency local oscillators were used, and a switched local oscillator followed by {aefiltration was used for the secondary transformation. and detection.